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Dear Mr. Kut... [message #9148 is a reply to message #9145] |
Thu, 04 August 2005 16:37 |
Thrint
Messages: 43 Registered: May 2009
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Baron |
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I don't think it was spam. The same circuit can be done with valves or SS. Like I said, I built the circuit which lead to this with valves. I have designed some stuff which was quite well recieved in these parts with a mix of SS and valves( Guinevere and Merlin ). Is there anything else you'd care to take issue with? There is plenty of SS in both of those designs, BTW. regards, Douglas
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Re: Super simple linestage. [message #9149 is a reply to message #9143] |
Thu, 04 August 2005 16:44 |
Thrint
Messages: 43 Registered: May 2009
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Baron |
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Which would you perfer? The valve circuit can be done with a +/- 200V supply fairly easily with cheap valves. For the input circuit, a triode strapped 6EJ7 and a pentode rigged 6EJ7 would be great. ~$3/tube too Now for the CCS for this cascoded cathode follower to work into. Single pentode perhaps? 6CL6 or an EL84 or any of the similar sized 9-pin pentodes would do. One could get nuts with a regulated g2 supply, but a dropping R and bypass C would be quite good as well. The beauty of the MOSFET sol'n is that we could do it with +/- 30V and DN2540N5's. Or a -30 supply with a MOSFET cathode load and valves on top. This I am going to build soon. I have a request from a very good friend back in PA for just such an item. I think I'll do it with Intact Audio ( Dave Slagle ) Autoformer volume controls if he'll foot the bill... regards, Douglas
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Mine too... [message #9152 is a reply to message #9151] |
Sun, 07 August 2005 19:34 |
Thrint
Messages: 43 Registered: May 2009
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Baron |
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Went through the shelf of Iron and parts: 1.5A/54.5-0-54.5 volt power TX. Full bridge, CT grounded 2x 15 Hy/75 mA Hammond chokes( mmmmmmhhhh, matched pair! ) coffee tin of 120 uF photo flash caps 50k, Audio taper Noble pot Sleeve of DN2540N5 Mosfet's 6 uF/220VAC Vit-Q AC caps for output coupling.The PS will yeild about +/- 40V. I think I'll try a 10 mA idle current for less than 1/2 Watt dissipation per top MOSFET and run w/o heatsinks. I have everything but the plate to mount to. Looks like a nice simple job at this time now. I can't wait to get it underway so I can put it In-System and see how it compares to the All-Valve version. See anything I missed? Diodes? Anybody have some nice diodes? 200 PIV/2A Schottkey? mmmhhhhh, no heaters! regards, Douglas
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Re: Dear Mr. Kut... [message #9153 is a reply to message #9148] |
Mon, 08 August 2005 14:16 |
Rek_O_Kut
Messages: 4 Registered: May 2009
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Esquire |
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>The same circuit can be done with valves or SS. That's true of most fundamental concepts, but entirely irrelevant. Solid-state designs are inappropriate to this forum.
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Can you explain... [message #9154 is a reply to message #9153] |
Mon, 08 August 2005 15:14 |
Damir
Messages: 1005 Registered: May 2009
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Illuminati (2nd Degree) |
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...what % of some design/amp can be SS, if any? I must confess that I used SS diodes sometimes, even IC voltage regulators, some transistor here and there (CCS)... But, the worst sin I`ve ever done was the guitar amp, entirely SS. Preamp 741 op-amps, then 5-band graphic EQ with about 7 other evil op-amps, and output stage with STK025 IC. Even PS for the preamp & EQ was transistors regulated, +/- 10V, BC141/BC161... Then 10-band VU-meter with LEDs, I don`t remember what IC... Sorry, I was young - it happened almost 25 years ago... Anyway, I`m glad that I had a chance to confess it here, bye...
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Re: Dear Mr. Kut... [message #9156 is a reply to message #9153] |
Mon, 08 August 2005 16:28 |
Thrint
Messages: 43 Registered: May 2009
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Baron |
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>>>That's true of most fundamental concepts, but entirely irrelevant. Solid-state designs are inappropriate to this forum. Well, you're entirely entitled to your opinion, no matter hwo wrong it appears to me. So where do you draw the line for being Tube PC( assuming that the term is even valid ). regards, Douglas
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mandatory change [message #9158 is a reply to message #9157] |
Tue, 09 August 2005 04:34 |
Thrint
Messages: 43 Registered: May 2009
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Baron |
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*NOT*.... but a +/- 40 volt power suply can be done with a vacuum rectifier diode. A pair of 6AX6 will do nicely. There's another from the Hy-G-300 Red Bank series in 9-pin for building a full wave bridge, the 6754. regards, Douglas
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